1) Field of the Invention
The present invention relates to a technology to reduce communication cost for remote maintenance of the internetwork connector and to build a trouble-resistant remote monitoring system.
2) Description of the Related Art
Recently, a considerable number of computer networks have been built with the spread of the Internet. Since malfunctioning of internetwork connectors such as routers, hubs, and switches that connect the computer networks with each other seriously affects the computer network, a maintenance of such connectors is of great importance.
Normally, the maintenance of the internetwork connectors is performed by directly connecting a monitoring apparatus located in a remote area with the respective internetwork connectors using an information network system (INS) or an exclusive line, such that the monitoring apparatus obtains data from the internetwork connectors via the connecting lines (see for example, FIG. 1 and page 3 of Japanese Patent Application No. 11-219388, FIG. 1 and page 3 of Japanese Patent Application No. 8-293918).
Another approach is to directly connect the monitoring apparatus with a predetermined internetwork connector, so that the monitoring apparatus exchanges data with other internetwork connectors via LAN (Local Area Network) and the predetermined internetwork connector (see for example, FIG. 1 and page 3 of Japanese Patent Application No. 2002-14881).
However, with the direct connection of the monitoring apparatus located in a remote area with the respective internetwork connectors via the INS or the exclusive lines, the number of the INS or exclusive lines to be used increases with an increase in the number of the internetwork connectors, resulting in an increase of the communication cost.
Furthermore, in order to connect a monitoring apparatus with an internetwork connector located in a remote area via the INS or the exclusive line, it is necessary to fix the monitoring apparatus at a place connectable with the INS or the exclusive line, thereby the place to be maintained is limited.
Even when it is desired to collect information at the same time by transmitting a command to a plurality of internetwork connectors simultaneously, since a single operation can transmit the command to only one internetwork connector, the command is transmitted sequentially to the internetwork connectors, resulting in a time-delayed collection of the information.
When a monitoring apparatus is directly connected with a predetermined internetwork connector, so that the monitoring apparatus exchanges data with other internetwork connectors via the LAN and the predetermined internetwork connector, if there is a problem with the LAN connection between the predetermined internetwork connector and the other internetwork connectors, the maintenance of the other internetwork connectors cannot be performed.